Gadgets that fade away when they're no longer useful is one goal of researchers working on transient materials. Knowing when such a material will dissolve is critical to making degradable composites practical for electronics implanted as part of surgical procedures, creating environmental sensors that dissolve into nontoxic materials when their useful lives have passed, or keeping tons of other gadgets from piling up in landfills, according to Reza Montazami, assistant professor of mechanical engineering at Iowa State University. His study on the stability and triggered dissolution of materials that would make an effective substrate for transient electronics was published by the journal Advanced Functional Materials on April 1.

For years, surgeons have used sutures, staples, and other supplies made of materials such as polyglactin and polyglycolic acid that disappear at predictable rates after being exposed to water or to enzymes and phagocytes in human tissue.

The idea of using transient material for electronics was popularized by the work of researchers at Tufts University and Northwestern University. A September 2012 paper in the journal Science described a technique that produced field-effect transistors, resistors, diodes, a heater, and a strain sensor made of material coated in magnesium oxide and layered in silk that worked properly and dissolved on schedule in both test tubes and mice. The goal was to produce devices that could be implanted in the body, received outside power through induction coils, and dissolved completely without poisoning the patient or having to be removed by surgery.

"These devices are the polar opposite of conventional electronics whose integrated circuits are designed for long-term physical and electronic stability," Fiorenzo Omenetto, professor of biomedical engineering at Tufts School of Engineering and one of the paper's authors, said in a Tufts press release. "Imagine the environmental benefits if cell phones, for example, could just dissolve instead of languishing in landfills for years."

Montazami's team built a series of degradable components for the study, including a data-transmitting antenna, resistors, capacitors, and LEDs. However, their real advance was the development of a polymer composite film that can act as a substrate for integrated circuits and can be programmed for different physical properties and dissolution speeds based on the materials used with or layered on the polymer.

"The resistors, capacitors and electronics, you don't expect everything to dissolve in such a manner that there’s no trace of it," Montazami said in an Iowa State press release.

Dissolving electronics could reduce e-waste or for devices to be implanted in the human body. Implanting packets of solvent into smartcards or other devices made with transient electronics could protect them from being stolen. A "kill switch" would puncture the solvent container to destroy, not only any sensitive data, but also the guts of the device itself.

If the proposed dissolvable electronic project has been keenly looked into considering both health and environmental issues, then I believe it is a good idea. If the gadgets can fade away when their life span is over then it will help solve the problem of pollution arising from electronic stuffs.

While the object of reducing waste is noble, the solution of building is self destruction isn't satisfactory to anyone. To the user, having several more guaranteed modes of failure certainly doesn't make the product more effective. While one mode of decomposition may take years under a "normal" environment, certain environments may very well accelerate it, causing warranty heaadaches for the manufacturer. I think a far more practical approach would be to aim for an efficient recycling process. Wouldn't if be nice to be able to simply dip the spent product into a magic potion, with a bit of electrolysis, that would separate the components into reuseable chemical compounds.

It is interesting to note that while many technology companies, especially in the less developed countries, are working intensely to increase the lifespan of electrical gadgets and devices so that their owner can use them longer, ours seem to be focusing more on making their lives shorter. Personally I subscribe to the first field of though and I still have a Pentium II computer in my garage that still works and which I boot up once in a while just for the kick of it. I would rather lose my Smartphone and then block it that have it with me only for it to be rendered useless within a few years.

I know that some phones have a water sensor inside that the manufacturer can use to deny warranty claims when they can prove the phone got wet. It is scary to consider that now the phone will simply dissolve when it gets wet. I guess I got spoiled when my wife's Motorola pager was run through the washing machine 26 years ago. When it was retrieved, we opened up the pager, removed the battery, and left it out to dry. The next day, we replaced the battery and the pager worked perfectly. I'd vote for reliable electronics and a comprehensive electronics recycling program.